Oil pressure control and filter for hydraulic presses



Jan. 19, 1932. T. J. MCNULTY OIL PRESSURE CONTROL AND FILTER FOR HYDRAULIC PRESSES Filed June l, 1929 2 Sheets-Sheet l j@ Inf/(Lf.

3mm/woz:

Jan. 19, 1932. T, J. MCNULTY 1,841,492

OIL PRESSURE CONTROL ANVD FILTER FOR HYDRAULIC PRESSES 2 Sheets-Sheet 2 Filed June l, 1929 2o press cloth;

25 take the place ofthe usual automatic-change Fig. ll iS a Similar vieu7 Withthe lower 75 r 35 press cloth.

`Patented Jan. 19, 1932 y :.1-

@rares ret-reni# TiioMs'J. mcnnrriprnooiznnvnn, MISSISSIPPI l oIL rnEssURn CONTROL Ann rIL'rEn'ron HYDRAULIC raEssEsy `Amener-,imi fired June 1, 192s.v serial- No. 367,819.

t My invention is'anV improvement inV hy- YFigure 1 is an elevation ot the combined draulic presses used in oil mills in the operaoil filter and pressure control in accordance tions of forming the cake as Well as extract- With: my invention.` Y 1 .ing the oil from the cake, and relates more F ig. 2 isa vertical sectional vieu7 through .5 especially to means for controllingfthe oil the same. f v 55 pressure to the ram. Y e t F ig. 3 is a transverse sectional View on the `The modern practice'in oil mills is to, opline S-Srot Fig. 2.A erate theram under aloW pressure of oil up Figal is a detail view of one of the perto a predetermined point and-then continue forated disks forming a part of the filter.

io the Aoperation under a high pressure of the Fig. 5 is a. detail View of one of the iilter- 6o oil, vfor which purpose it is-.customary to eming screens. l

. ploy automatic` change valves by Which to Fig is a detail sectional View of the casregulate the pressure inthek 'formation of the ing with the closing cap detached from the cake and expressing the oil therefrom, but I body. n

15 hay/@found bypractical .experience there is F 7 iS .3. detail SeCiOIl'al VlW'O the Oil 65 no need of using two different pressures in pressure control device used in connection the line to the pressasvalconstant flow up to With the filter.

500 pounds Will give the desired result in the Fig. S is a detail View, partly in section,

Aextraction of the oiland aiiord a saving) in Showing4 av modication ott4 the basket vcony v taining the filtering material. 7 The primary object of my invention there- Fig. 9 is a sectional View on the line 9 9 tore is to'provide aconstant regulated Aflow 0f Fig. 8- v l y of Oil t0 the ram ,by means 0f ,a Combined' Fig. l0 iS an elevation illustrating amOClilter and pressure control device that will ication in the construction of the casing, and

valves5`the latter being'not only unreliable portion of the casing broken away to-shoW in operation but subject to considerable Wear the arrangement of the inlet and outlet openaiecting the Working of the pressas well as ings. v f f y adding to the cost of operation, the com- My invention is especially adapted for use 3o billedV filter and kflow eem-,1101 in `thepresent in connection With oil mills ink which a hygg instance .producing L fluency of the 011 which vdraulic motor employing oil as the fluid pres-. Will provide a continuous pressure imparting Sure. is used with ka pump driven by motive a gradual steady rise to the framto increase power such'as a steam engine, the combined the eciency. of the press andpreserve the filter and pressure controly device being incor- .V Y. porated in thepipe line to the pump. .Y 85 ith this principal. object in view my in- In carrying out my invention the casing vention contemplates theprovision of a de- Which contains the -Ltilter and meansfor convice to beincorporate'd in the pipe line to the' trolling the oil pressure .comprises a body press by meansof which theloil is forced portion 14 and removable `cap 15, the body '40 through .filtering material and Aiine mesh portion 14E having integral coupling members eo screens for passage throughy a smalloritice 16 andv 1T at opposite sides of the lower end by which theiiovv to the press is controlled', thereof into Which'pipes 18 and 19 leading the size of the orifice determining thespeed to and from the Vcasing are threaded and of operation ofthe ram. Within said body portion is a filtering cham- 145 V'My invention furthercontemplatesa parber 2O through the bottom of which extend 95 ticular construction of the combined oil filter openings 21 and 22 communicating, With the and pressure control; all as hereinafter fully outlet 17 and inlet lrespectively, opening described and morespecitically set forth in 21 being located centrally and threaded to the-appended claims. t v receive the pressure control device hereini ..59 n'the accompanying drawings i'. t iafter described. The upperpart of the filter 10o chamber is enlarged to receive a perforated annular disk 23 resting on the shoulder 2st formed by enlarging the chamber, and upon this disk are placed fine mesh screens 25 and 26, one upon another, held in place by a second perforated annular disk 27 the upper surface of Which is approximately fiush with the upper end of the body portion of the casing, the aforementioned perforated disk 23 being provided With an annular groove 23a (Fig. ff) in the side thereof next the screen mesh. The oil passes up in the filtering chamber 2O to the disks and screens hereinbefore mentioned through filtering material 28, and extending upward through the center of this filtering material, disks, and screens, is a tube 29 threaded at its lower end in the opening 2l and provided at its upper end with a nipple 8O having a small orifice or inlet opening 3l (F ig. 7) ,the nipple beino` preferably detachable and therefore threaded into the upperend of the tube so that it may be readily removed for substitution of a nipple having an orifice of a different size or in case the orifice in said nipple should become Worn from use. The nipple projects above the upper disk 27 of the filtering device into a cavity 32 in the cap 15, said cavity forming a reservoir for the oil with the upper or inner end thereof tapered and the end of the nipple located a suitable distance from the apex, and for the purpose of forming a tight joint between the cap and upper end of the body portion of the device leather gaskets 33-33 are interposed as shown in ig. 2 of the drawings.

The filtering material 28 in the casing is enclosed ina Wire screen basket 84 for convenience in removing the same, the modifi-- cation in Fig. 8 including an inner lining 35 of Wire screen to fit around the central tube 29 of the pressure control device, and for cleaning said ltering material While it is contained in the filtering chamber a. cleanout opening 36 is provided in one side of the casing on a line with the bottom portion of said chamber and normally closed by av valve nipple (not shown). The filtering material is preferably press cloth darning yarn though of course any other suitable material may be used, and the Wire screen mesh between the annular disks 23 and 27 is very fine, about 120 mesh, so as to strain the oil of any foreign matter that may pass through the filtering material and thus preventchoking of the orifice in the nipple which is approximately .5G/100() of an inch for a high pressure feeding line and g to g3g of an inch in the loW pressure line; it being understood of course that filtering and pressure control devices of my invention are located in both lines leading to and from the hydraulic motor or ram.

As a modification of the casing the inlet opening may be located on aline with the bottom of the filtering chamber, as illustrated in Figs. l0 and ll of the drawings, in which 37 designates the coupling for the pipe 38 leading to the opening into the filtering chamber and 39 the coupling for the pipe a() communicating with the passage from the lower end of the, tube 29 of the pressure control, other- Wise the device is the saine as that described With reference to Figs. l and 2, like numerals of reference being used for like parts in both forms.

The operation of my improved means for controlling the fluid pressure of the oil to the ram Will be understood from the foregoing description, for the oil from the storage tank entering the device through the inlet 16 and passing through the filtering material 28 and Afine mesh screens 25 and 26 is purified of any foreign substances,-as foots, or grit from the packings of the pump,-.-and Will flow freely through the reducing orice in the nipple 30 to the tube 9.9 and on to the ram through pipe 19 of the pipe line, the size of the orifice governing the pressure of the oil on the ram and preventing any danger of the oil fiowing so fast as to cause the pump to run away. As will be obvious the filtering of the oil will eliminate the possibility of the orifice becoming choked, and consequently as there will be a steady flow of the oil the presses will travel the full height at all times resulting in a better extraction from the oil bearing mea-ts or cake thus in creasing the out-put of oil from the same.

The filtering material in the chamber of `the casing can be cleaned or flushed out b Y removing the cap and blowing out through the clean-out openinghaving the valved nipple, or the filtering materiai may be renewed by simply removing the basket and replacing it With another one having the packing confined between the cylindrical Wire screens forming the basket, the inner screen or lining 35 facilitating the insertion of the confined packing over the tube. Furthermore, the rate of flow through the reducing orifice in the removable nipple may be varied according to operation desired by substitut-ing a nipple having the required orifice.

I have herein shown and described the preferred embodiment of my invention, but it Will be understood that changes or modifications in the form of the device or arrangement of parts may be resorted to Within the scope of the claims in carrying-out the purpose to provide for thoroughly filtering the oil and reducing the flow to the ram by a minute orifice through which the oil passes in a fine steady stream to produce the re' quired pressure for amore effective operation of they press.

I claim:

l. In a hydraulic press a device for controlling the pressure of oil to the ram comprising a casing having a body portion forming a filtering chamber open at itsupper end, inlet and outlet openings through the casing at the closed end of the filtering chamber, a removable cap closing the open end ofthe ltering chamber and forming a reservoir, a tube extending from the outlet opening through the ltering chamberinto said reserv voir a nipple on the end of the tube having a minute oriiice to control the pressure of oil flowing from the casing to the ram, a libre packing in the lower portion of the ltering chamber, annular perforated disks above the-- libre packing and through which the tube passes, and fine mesh screens interposed between the annular perforated disks.

2. In a hydraulic press a device for controlling the pressure of oil to the ram comprising a casing having a body portion forming a filtering chamber enlarged at its upper open end to form a shoulder, said casing having inlet and outlet openings at its Vlower end, the outlet opening beingcentrally located, a removable cap closing'the upper end of the casing and forming a reservoir at the z5 upper end of the ltering chamber, a tube connected to the outlet opening and extending upward at the center of `the ltering chamber into the reservoir in the cap, and a nipple on the end of the tube having a minute 3G orifice to reduce the pressure of oil flowing into the tube;,together with a packing in the lower portion of the filtering chamber, perorated annular disks resting on the shoulder in the upper end of said chamber and through which th-e tube passes, and fine mesh screens interposed between the perforated disks.

THOMAS J. MCNULTY. 

